Clutch drive



Aug. 8,1950 B. B. KORN CLUTCH DRIVE Filed Dec. a, 1948 BERNARD B. KO/PN.

IN VEN TOR.

A T TORNEK Patented Aug. 8, 1950 UNITED STATES PATENT OFFICE CLUTCH DRIVE Bernard'B. 'Korn, Los Angeles, Calif.

Application December 6, 1948, Serial No. 63,750

applyingclutch pressure through the bearing,

without thereby adding any drag to the shaft.

'lAnother object is to provide an accessible adjustable clutch spring for an inaccessible clutch.

A further object of the invention is to provide an improved form of bracket for supporting the clutch in operative relation to a driving motor as well as an improved mount for an idler pulley for taking up slack in a belt between the motor and the clutch drive.

For further details of the invention reference may be made to the drawings wherein:

Fig. l is a rear view in elevation of a motion picture printer having the clutch drive and bracket of this invention.

Fig. 2 is an enlarged sectional view on line 2-2 of Fig. 1 looking in the direction of the arrows.

Fig. 3 is a sectional view on line 3-3 of Fig. 1

looking in the direction of the arrows.

Referring in detail to the drawings, the motion picture printer I comprises a casing 2 having a rear wall 3, with a film supply magazine 4 at one end of the casing 2, and a film take-up magazine 5 at the other end of the casing. Film magazine 4 has a coupling 6 for an upper reel of raw stock, and a coupling 7 for a lower reel of developed film to be printed on to the raw stock. The magazine 5 has an upper coupling 8, see Fig. 2, for the take-up reel for the raw stock, and a lower coupling similar to 8 to take up the other film.

The nature of the film drive and printing gate in the casing 2 form no part of the present invention. The film drive includes one or more driven sprockets not shown which are driven by a motor 9 having a suitable reduction gear in a housing indicated at H), such gearing terminating in a drive pulley II between the reduction gear l6 and the rear wall 3'. Pulley Ilis provided with a belt I2 which passes around the pulley l3 for coupling 8 'and around pulley I4 for the lower coupling similar to 8. That portion of the belt [2 intermediate the pulleys l3 and I4, passes around an idler pulley I5 which is adjustable to take up slack.

Pulleys I3, l4 and. I5 are mounted on a bracket I6. Bracket I6 ha at the rear thereof an angle 2 Claims. (01'. 64 30 flange H which fits the vertical face I B-of the reduction gear housing II], being secured thereto by bolts like I3.

The bracket I6 is an open unitary frame-work somewhat in the form of a trapezoid whereinthe inner vertical flange I1 is parallel to the outer side or arm 26, the pulleys I3 and I 4- being arranged at the top and bottom, respectively, of the arm 26, with arm 20 braced by the inwardly sloping sides 2! and 22 which merge with the top and bottom, respectively, of the flange I I'. The pulley I5 is supported by a cross arm 23 extending from the side 20 to the flange H where it joins with the side 2|. Pulley I5 has an axle 24 which is adjustably held in an elongated slot 25 in the arm 23 by a nut 26.

The clutch drive for the pulley I3 is the same as the clutch drive for pulley l4, and only the drive for pulley I3 will be described in detail. Pulley I3 is loosely mounted on a shaft 36, the latter being rotatably and slidably supported by ball bearings 3|, 32 slidably mounted in a bearing support 33' on the bracket I6. Ball bearing 3| has an inner race 6 I, and an outer race I I. Bearing 32 has an inner race 62 and an outer race 12. Between the bearings 3| and 32 is a separator stop ring 34 removably held in position in bearing support 33 by a screw 35. Separator 34 is shorter in an axial direction than a spacing ring 36 between and abutting the adjacent surfaces of the inner races 6|, 62 so that when spring 56 applies a force to one of the races 6!, 62 to slide it along the shaft 30, such force will be communicated through ring 36 to the other race to slide it a like amount.

Adjustable clutch pressure is applied to the outer race 62 by a compression spring 56 around shaft 36 and bearing on a spring follower in the form of a disk 3"! which bears on the outer face of race 62. The shaft 36 is threaded at its outer end as indicated at 38 and provided with a nut 39 serving as a stop for the outer end of spring 56. Nut 39 has a suitable lock screw 40. The inner face of the race 6| bears on the hub 55 of a clutch plate 4!. Plate 4| is slidable on shaft 30 and keyed thereto by a key 42 in the shaft 30 and a cooperating axial slot 43 in the clutch plate 4|. A disk 44 of suitable frictional material is arranged between the inner face of plate M and the outer face of pulley I3 and a similar disk 45 of frictional material is arranged between the inner face of pulley l3 and the outer face of a coupling member 46 fixed to shaft 30 by a set screw 21. Coupling member 46 has a pair of axially extending and diametrically opposite pins 41 and 48 removably receiving corresponding apertures 49 and 59 in rubber insert 51, 52, respectively, in the coupling member 8 which is fixed to the spindle 53 of the take-up reel 54.

It will be apparent, therefore, that the coupling member 46 serves as an abutment fixed on the shaft 30 for all of the remaining elements of the clutch as well as inner races 6!, 62, all of which are slidable on the shaft 30 and held under a suitable pressure by the spring 56.

As a result of the above construction, the nut 39 can be adjusted to adjust the force of spring 56 to vary the slippage of pulley I3, i. e., the pressure of the clutch 4|, 44, i3, 45, 46. Such spring pressure does not add any braking effort to the rotation of shaft 30 which is free running, as the spring pressure acts on clutch plate 4| through the inner races El, 62 which revolve with the shaft 30, and not through the outer races ll, 12 which do not revolve in their bearing support 33. Also the invention provides a very compact arrangement wherein the coupling 8, pulley l3 and bearing support 33 are closely spaced together, with the adjusting nut 39 readily accessible, although plate 4! is not.

The magazines 4 and 5 are removably mounted on the casing 2 by suitable means not shown. The magazine 5 is uncoupled from its clutch drive by moving it in a plane parallel to itself, to withdraw the coupling members like 8 from their pins like 49 and 50.

The spring 56, as is well known, is adjusted to 4 have a tension such that the pulley I3 will slip before the film breaks.

Various modifications may be made in the invention without departing from the spirit of the following claims.

I claim:

1. A clutch drive comprising a rotatable shaft having a bearing support, a coupling member fixed to said shaft, a power transmission device rotatable on said shaft," for said coupling member, and'a movable clutch element for said device and said member on one side of said bearing REFERENCES CITED The following references are of record in the file of this patent:

, UNITED STATES PATENTS Name Date Ress Jan. 9, 1945 Number 

